Purpose: To divide fractions. Homework: P. 256 – – 43 odd
Example #1 You already know how to multiply fractions. To divide you leave the first expression the same, change ÷ to x and reciprocate (FLIP) the fractions following the division sign. 2p ÷ 8p = 2p 5q **finish by x q 5q q 8p (4) = 5/4
Example #2 5t – 10 ÷ t – 2 **Factor, change ÷ to x. t – 5 2 **Flip the 2nd fraction. 5(t – 2) 2 t – 5 t - 2 **Cancel and multiply. 10 t – 5 is the answer.
Example #3 y² + 3y – 10 ÷ 2y – 4 y² - 16 y + 4 ALWAYS FACTOR!!!! (y + 5)(y – 2) y + 4 (y + 4)(y – 4) 2(y – 2) **Cancel and X. y + 5 2(y – 4) is the answer.
Example # 4 On these problems, you need to do exponents first. a² 2a ÷ (a)³ a² 2a b³ b b (b)³ = b b a³ a² 2a b b b b b a² a = 2b
#44 p. 257 ALWAYS FACTOR FIRST!! (b+7)(b - 1) (2b - 5)(b +3) (3b+ 4)(b - 2) (3b+4)(2b - 5) (b - 1)(b +3) (b + 7)(b -2) HINT: When trying to factor, try binomial pairs that you already have. Notice every pair cancels and the answer is 1.